Pneumatic tire having a film-shaped electronic device and method of mounting the film-shaped electronic device

ABSTRACT

A pneumatic tire having a film-shaped electronic device on a surface of the tire or inside the tire. The film-shaped electronic device is slidable between sheet-shaped members disposed on both surfaces of the film-shaped electronic device.

TECHNICAL FIELD

The present invention relates to a pneumatic tire having a film-shapedelectronic device and a method of mounting the film-shaped electronicdevice, and more particularly, to a pneumatic tire having a film-shapedelectronic device and a method of mounting the film-shaped electronicdevice, in which the film-shaped electronic device can be prevented frombreaking.

TECHNICAL BACKGROUND

In recent years, there is proposed a pneumatic tire having a transponderwhich has functions of a transmitter and a receiver to obtaininformation on identification of the pneumatic tire and information suchas pressure, temperature and rotation speed of the tire (for example,Unexamined Japanese Utility Model Publication No. 7-30104). Suchtransponders used for pneumatic tires comprise, in general, acylindrical glass protection container, a coil-shaped antenna, and anintegrated circuit for storing information, the antenna and integratedcircuit being contained in the glass protection container.

Pneumatic tires employing the transponder are very useful since variouspieces of information stored in the integrated circuit can easily beobtained as necessary. However, the cost of the above-structuredtransponder is high, and therefore, there is a problem of a greatincrease in the cost of the pneumatic tire.

In order to solve the problem, the present inventor produced a pneumatictire into which an inexpensive film-shaped transponder in general use (atransponder using a frequency band of 13 MHz standardized by ISO) wasembedded, and as a result, it was realized that the film-shapedtransponder was significantly inferior in durability to that using theglass protection container.

That is, there arises such a problem that, when air pressure is appliedto inflate the pneumatic tire fitted to a rim, the transponder fixed tothe pneumatic tire is pulled by inflation deformation of the pneumatictire and is broken.

DISCLOSURE OF THE INVENTION

An object of the present invention is to provide a pneumatic tire havinga film-shaped electronic device and a method of mounting the film-shapedelectronic device, in which the film-shaped electronic device can beprevented from breaking even if the film-shaped electronic device suchas an inexpensive film-shaped transponder is mounted on or inside apneumatic tire.

In order to achieve the above object, a pneumatic tire according topresent invention has a film-shaped electronic device on a surface ofthe tire or inside the tire, the film-shaped electronic device beingslidable between sheet-shaped members disposed on both surfaces of thefilm-shaped electronic device.

A method of mounting a film-shaped electronic device according to thepresent invention comprises the steps of forming a film-shapedelectronic device containing sheet assembly having sheet-shaped membersand an electronic device slidably contained between the sheet-shapedmembers, and fixing the film-shaped electronic device containing sheetassembly inside or to a surface of an uncured tire, or to a surface of acured tire.

According to the present invention described above, when air pressure isapplied to inflate the pneumatic tire, the sheet-shaped members arepulled and deformed with inflation deformation of the pneumatic tire.However, the film-shaped electronic device moves between thesheet-shaped members, and therefore, the film-shaped electronic devicedoes not receive influences of the tensile deformation. Also, when thepneumatic tire is deformed by compression during traveling, influencesthereof on the film-shaped electronic device can be avoided.Accordingly, the film-shaped electronic device mounted on or inside thepneumatic tire can be prevented from breaking, and the inexpensivefilm-shaped electronic device is available.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a main cross-sectional view showing an embodiment of apneumatic tire according to the present invention.

FIG. 2 is an enlarged cross-sectional view of the film-shaped electronicdevice containing sheet assembly in FIG. 1.

FIG. 3 is a plan view of the transponder in FIG. 2.

FIG. 4 is a main enlarged cross-sectional view of the transponder inFIG. 2.

FIGS. 5 a and 5 b are a plan view and a cross-sectional view forillustrating a step before an uncured tire to the side wall outersurface of which the film-shaped electronic device containing sheetassembly adheres is set to a mold of a curing press.

FIG. 6 is a plan view showing an example of a transponder on the surfaceof which information for identifying a tire is indicated.

BEST MODES FOR CARRYING OUT THE INVENTION

The embodiments of the present invention will be described in detailbelow with reference to the drawings.

Referring to FIG. 1, there is shown an embodiment of a pneumatic tirehaving a film-shaped electronic device according to the presentinvention, in which reference numeral 1 denotes a tread, referencenumeral 2 denotes a sidewall, and reference numeral 3 denotes a bead. Acarcass ply 4 is disposed between the left and right beads 3, and eachend portion 4 a thereof is turned up around a bead core 5 from the innerside of the tire towards the outer side so as to sandwiching a beadfiller 6. A plurality of belt plies 7 are provided radially outwardly ofthe carcass ply 4 in the tread 1, and a plurality of belt cover plies 8are placed radially outwardly of the belt plies 7. An inner liner ply 9is provided inwardly of the carcass ply 4.

Fixed between the carcass ply 4 and the inner liner ply 9 inside thebead 3 of the tire is a film-shaped electronic device containing sheetassembly 10 in which a film-shaped transponder 20 (see FIGS. 2 and 3) iscontained.

The film-shaped electronic device containing sheet assembly 10, as shownin FIG. 2, comprises two sheet-shaped members 11 and 12 formed of amaterial that enables the transponder 20 to be slidable, and allperipheral edges of the two sheet-shaped members 11 and 12 which areoverlapped to each other are bonded to each other to thereby form asealed room 13 between the two sheet-shaped members 11 and 12. Thetransponder 20 is placed in the room 13, and is slidable between the twosheet-shaped members 11 and 12 which are disposed on the both surfacesof the transponder 20. The sheet-shaped member 11 is completely adheredto the inner surface of the carcass ply 4, and the sheet-shaped member12 is completely adhered to the outer surface of the inner liner ply 9.

A transponder employing a frequency band of 13 MHz standardized by ISOis used for the film-shaped transponder 20, and as shown in FIG. 3, thefilm-shaped transponder 20 includes a base film 21 formed of resin suchas polyimide, nylon or polyethylene terephthalete, an coil-shapedantenna 22 formed on one surface 21 a thereof by printing, and anintegrated circuit 23 affixed to the surface 21 a by brazing or thelike.

As shown in FIG. 4, laminated on the surface 21 a of the base film 21via an adhesive layer 24 is a protection layer 25 formed of the samematerial as that of the base film 21. It is preferable that thetransponder to be mounted in the tire be in the range of 0.2 to 0.8 mmin thickness.

The antenna 22 of the transponder 20 is connected to the integratedcircuit 23, and various pieces of tire identification information storedin the integrated circuit 23 can be read via the antenna 22 by areading/writing device (not shown) for the transponder 20, and newinformation can be stored in the integrated circuit 23 by thereading/writing device.

The above-mentioned transponder 20 is mounted inside the pneumatic tireas follows. First, the transponder 20 is placed between the sheet-shapedmembers 11 and 12 in a sandwiched fashion, and the peripheral edges ofthe sheet-shaped members 11 and 12 are then adhered to each other tothereby form the film-shaped electronic device containing sheet assembly10 containing the transponder 20 slidably in the room 13 between thesheet-shaped members 11 and 12.

The film-shaped electronic device containing sheet assembly 10 isadhered onto the inner liner ply 9 after the inner liner ply 9 is woundaround a tire building drum in a conventional uncured tire manufacturingprocess, and the film-shaped electronic device containing sheet assembly10 is placed inside an uncured tire. The uncured tire is cured tothereby obtain the pneumatic tire of FIG. 1.

According to the present invention mentioned above, when air pressure isapplied to inflate the pneumatic tire which is assembled to a rim, thesheet-shaped members 11 and 12 are pulled with inflation deformation ofthe pneumatic tire. The transponder 20, which is slidable between thesheet-shaped members 11 and 12, is not deformed by the pulling, sincethe transponder 20 moves between the sheet-shaped members 11 and 12 inaccordance with the inflation deformation of the pneumatic tire.

Also, when the pneumatic tire is deformed by compression duringtraveling, influences thereof on the transponder 20 can be avoided sincethe transponder 20 is movable between the sheet-shaped members 11 and12. Accordingly, the film-shaped transponder 20 mounted in the pneumatictire can be prevented from breaking. Therefore, the inexpensivefilm-shaped transponder 20 which employs a frequency band of 13 MHzstandardized by ISO is available, and the cost of the pneumatic tirehaving the transponder does not increase significantly.

In the present invention, it is preferable that the transponder 20 beprovided between the carcass ply 4 and the inner liner ply 9, asdescribed above, in terms of the minimum affection of tensile andcompressive deformation of the tire on the transponder 20. However, itis not limited thereto. For example, the transponder 20 may be placedbetween the carcass ply 4 and a rubber portion of the sidewall locatedoutwardly of the carcass ply 4.

In this case, the transponder 20 is mounted as follows. In theconventional uncured tire manufacturing process, the carcass ply 4 iswound around a tire building drum, and the film-shaped electronic devicecontaining sheet assembly 10 containing the transponder 20 is thenadhered onto the carcass ply 4 to be placed inside the uncured tire.

In the above embodiment, an example is shown of the case where thefilm-shaped electronic device containing sheet assembly 10 containingthe transponder 20 is fixed inside the tire. In the alternative, thefilm-shaped electronic device containing sheet assembly 10 containingthe transponder 20 may be fixed on a surface of the tire, as shown inFIG. 1.

The tire surface may be an outer surface T1 of the tire or an innersurface T2 of the tire. In the case of the tire outer surface T1, thefilm-shaped electronic device containing sheet assembly 10 containingthe transponder 20 is preferably fixed to the sidewall 2, and in thecase of the tire inner surface T2, the film-shaped electronic devicecontaining sheet assembly 10 containing the transponder 20 may be fixedto the sidewall 2 or bead 3.

The transponder 20 is mounted on the tire surface as follows. Thefilm-shaped electronic device containing sheet assembly 10 containingthe transponder 20 is bonded to the surface of a cured tire with anadhesive or the like, or is adhered to the surface of an uncured tirebefore set in a tire press.

In the case in which the film-shaped electronic device containing sheetassembly 10 is adhered to the outer surface of an uncured tire, theuncured tire is preferably set in the mold of a tire press as follows tobe cured.

In general, the outer surface of the sidewall 2 has concavo-convexpatterns showing a manufacturer's name and the like, and the film-shapedelectronic device containing sheet assembly is preferably fixed to alocation where no concavo-convex part exists. As shown in FIG. 5, beforean uncured tire Tu is set in the mold of a tire press, the uncured tireTu is placed on a rotation table 30 in the same state as lying on itsside when set in the mold, with the film-shaped electronic devicecontaining sheet assembly 10 being positioned on the upper side thereof.A reading antenna 31 for the transponder 20 is placed thereabove, andwhen a rotation mechanism 32 rotates the rotation table 30, the readingantenna 31 receives a reply signal sent from the transponder 20 in thefilm-shaped electronic device containing sheet assembly 10 adhered tothe uncured tire Tu rotating with the rotation of the rotation table. Acomputer (not shown) connected to the reading antenna 31 indexes theposition of the film-shaped electronic device containing sheet assembly10 based on the reply signal, and stops the rotation after adjusting theposition of the film-shaped electronic device containing sheet assembly10 on the basis of data previously input in the computer so as to be ina location where the concavo-convex patterns are not formed. The uncuredtire in the adjusted state is carried and set in the mold by a loader(not shown), and is cured.

In the case where the film-shaped electronic device containing sheetassembly 10 is fixed to the tire outer surface T1, as shown in FIG. 6,information I identical to the tire identification information stored inthe integrated circuit 23 may be indicated on the outer surface 20 a ofthe transponder 20. This allows for obtainment of the tireidentification information without a reading device for the transponder20.

In the drawing shown, the information I is shown with numerical andalphabetical characters into which the contents of the information I arecoded, but may be shown with other characters. The color thereof may beany color if they can visually be made out. In the case where theinformation I for identifying a tire is shown on the outer surface 20 aof the transponder 20, at least one of the sheet-shaped members 11 and12 which is positioned on the front surface side thereof is formed of atransparent material in addition to a condition described later.

The sheet-shaped members 11 and 12 constituting the film-shapedelectronic device containing sheet assembly 10 may be formed of anymaterial if the transponder 20 is slidable and no bad affection is givento tire performances when fixed thereto, and are preferably formed of,for example, a resin having a melting point of 150° C. or more, and alow coefficient of friction in the form of the sheet-shaped member. Theresins may preferably include, for example, fluorocarbon resins. Thesheet-shaped members 11 and 12 may be formed from a sheet-shaped wovenfabric or knit fabric.

The transponder 20 may be slidable between the sheet-shaped members 11and 12 by coating a material which facilitates sliding of thetransponder 20 on the inner surfaces of the sheet-shaped members incontact with the transponder 20 when the sheet-shaped members 11 and 12are formed of a material which prevents the transponder 20 from sliding.

In the above embodiments, the pneumatic tire having a film-shapedtransponder 20 has been described, but the present invention is alsoapplicable to pneumatic tires having other film-shaped electronicdevices instead of the transponder 20.

As illustrated above, according to the present invention, thefilm-shaped electronic device which is slidable between the sheet-shapedmembers disposed on the both sides of the film-shaped electronic device,is mounted on the tire surface or inside the tire, and therefore, thefilm-shaped electronic device slides freely between the sheet-shapedmembers when pulled or compressed by deformation of the tire, thusavoiding influences of the pulling and compressing. Accordingly, even ifan inexpensive film-shaped electronic device is mounted thereon ortherein, it can be prevented form breaking.

INDUSTRIAL APPLICABILITY

The present invention having the aforementioned excellent effects isvery effectively applicable to a tire having a film-shaped electronicdevice.

1. A pneumatic tire having a film-shaped electronic device on a surfaceof the tire or inside the tire, the film-shaped electronic device beingslidable between sheet-shaped members disposed on both surfaces of thefilm-shaped electronic device, wherein two sheet-shaped members disposedon the both surfaces have peripheries bonded to each other to therebyform a room between the two sheet-shaped members, in which thefilm-shaped electronic device is slidable, and wherein the sheet-shapedmembers comprise a fluorine resin or respectively have an inner surfacecoated with such a material which permits the film-shaped electronicdevice to slide thereon.
 2. A pneumatic tire according to claim 1,wherein the film-shaped electronic device is a film-shaped transponderfrom which tire identification information can be read, the film-shapedtransponder comprising a base film, an integrated circuit and acoil-shaped antenna, the integrated circuit and coil-shaped antennabeing provided on the base film.
 3. A pneumatic tire according to claim2, wherein the film-shaped transponder is 0.2 to 0.8 mm in thickness. 4.A pneumatic tire according to claim 1, wherein the sheet-shaped membersare formed of a resin which has a meting point of 150° C. or more.
 5. Apneumatic tire according to claim 2, wherein the sheet-shaped membersare formed of a resin which has a meting point of 150° C. or more.
 6. Apneumatic tire according to claim 3, wherein the sheet-shaped membersare formed of a resin which has a meting point of 150° C. or more.
 7. Apneumatic tire having a film-shaped electronic device on a surface ofthe tire or inside the tire, the film-shaped electronic device beingslidable between sheet-shaped members disposed on both surfaces of thefilm-shaped electronic device, wherein the film-shaped electronic deviceis a film-shaped transponder from which tire identification informationcan be read, the film-shaped transponder comprising a base film, anintegrated circuit and a coil-shaped antenna, the integrated circuit andcoil-shaped antenna being provided on the base film, and wherein thefilm-shaped transponder is placed on an outer surface of the tire, atleast one of the two sheet-shaped members positioned on the frontsurface side thereof being formed of a transparent material, informationidentical to the tire identification information being shown on thefront surface of the film-shaped transponder.
 8. A pneumatic tireaccording to claim 7 wherein the film-shaped transponder is 0.2 to 0.8mm in thickness.
 9. A pneumatic tire according to claim 7 wherein thesheet-shaped members are formed of a resin which has a meting point of150° C. or more.
 10. A method of mounting a film-shaped electronicdevice, comprising: placing a film-shaped electronic device betweensheet-shaped members, the sheet-shaped members being formed offluorocarbon resin, or having inner surfaces coated with a material thatenables the film-shaped electronic device to slide between thesheet-shaped members, adhering peripheral edges of the sheet-shapedmembers to each other to thereby form a film-shaped electronic devicecontaining sheet assembly having a room between the sheet-shapedmembers, the film-shaped electronic device being slidably contained inthe room, and fixing the film-shaped electronic device containing sheetassembly inside or to a surface of an uncured tire, or to a surface of acured tire.